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Fencer Intel
high 7.2

CVE-2021-37770 json

Nucleus CMS v3.71 is affected by a file upload vulnerability.

published 4y ago modified 4mo ago also EUVD-2021-24251

cvss
7.2
version 3.1, NVD
cisa kev
Not listed
not in CISA's catalog
epss
1.3%
EPSS 1.3% chance of exploitation in 30 days, percentile 71%
public exploits
0
none known

Summary

Nucleus CMS v3.71 is affected by a file upload vulnerability. In this vulnerability, we can use upload to change the upload path to the path without the Htaccess file. Upload an Htaccess file and write it to AddType application / x-httpd-php.jpg. In this way, an attacker can upload a picture with shell, treat it as PHP, execute commands, so as to take down website resources.

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Exploit prediction

1.33% chance of exploitation in the next 30 days, higher than 71% of all scored CVEs (FIRST EPSS, 2026-11-09).

Exploits and checks

  • github.com https://github.com/NucleusCMS/NucleusCMS/issues/96 referenced PoC, tagged "exploit" by a source, unverified
  • shimo.im https://shimo.im/docs/Ch9CphJt8XwTvQ3d referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by version score vector
NVD 3.1 7.2 CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H
NVD 2.0 6.5 AV:N/AC:L/Au:S/C:P/I:P/A:P

Classification

Weakness
  • CWE-434 Unrestricted Upload of File with Dangerous Type

References

Sources

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.